For us, its all old fashioned sales.
Propensity to buy lists, solution selling then referrals.
Im not sure about these forums. It started as an experiment for us (WHT, HHO and now HT)..... but - I ended up finding real value in them for our business - nice to have a resource of professionals who are willing to share their experiences. We havent received many customers from the forums, but we have received a few. Most importantly, we have learned alot and met some great people 🙂